I went stargazing last night at Sandstone Peak in Malibu with my friend Huzaifa – here are some of the post-processed long-exposure shots he took:
Huzaifa has two scopes, and a local named Bob showed up with his own rig. All together, we viewed Saturn’s rings, Jupiter’s moons and bands, and Mars, not to mention a few Messier globular clusters, an open cluster in Hercules, and Berenice’s Comb.
Here’s the location – the ocean was due south, and offered the darkest skies, though we left around midnight, well before the bulk of the Milky Way rose. The western sky was a slightly contaminated by glow from Oxnard. Due east was pretty poor due to light from Thousand Oaks and the Valley beyond. The bulk of Los Angeles proper was southeast and too far away to really interfere, however. For a site only 30 min from home, this was an absolutely superb location, especially for the southeastern sky. See:
If time travel is possible, then the present is the past for an infinite number of futures. (Assuming the time stream is changeable by travelers, and not fixed).
In an infinite number of futures, there are a sub-infinity number of those futures in which a time traveler exists who finds today, the day you are reading this blog post, a fascinating and pivotal moment in history.
Therefore, even if only a small fraction of those infinite future travelers obsessed with our today actually bother/have the means to travel to today, there are still an infinite number of them.
Therefore, today there should have been an infinite number of time travelers appearing from an infinite number of different futures. Or, as Douglas Adams would have said, “whop”
Of course the same argument holds for every moment of every day in all of recorded history, so basically we should be inundated with infinite numbers of time travelers arriving at every moment of time for all time.
Since that is clearly not happening, time travel must be impossible.
I’d love to see a What-If XKCD on the idea of an infinite number of time travelers arriving today, actually… would probably be a mass extinction, the Earth would suffer gravitational collapse, and we’d be in a black hole. I think.
(In addition to MRI and medical physics, it’s worth keeping an open mind and keeping tabs on various other branches of physics and science. To that end, I’ll highlight interesting papers or research that strikes my fancy from time to time.)
Eric Berger aka SciGuy, a science columnist at the Houston Chronicle, points to a new paper in Science that introduces new “metamaterials” which can manipulate light, which are easy to fabricate (in principle). Eric makes the analogy to this being as much a game-changer as lasers were when they were invented almost exactly 50 years ago.
Here’s the abstract of the paper:
Self-Assembled Plasmonic Nanoparticle Clusters
The self-assembly of colloids is an alternative to top-down processing that enables the fabrication of nanostructures. We show that self-assembled clusters of metal-dielectric spheres are the basis for nanophotonic structures. By tailoring the number and position of spheres in close-packed clusters, plasmon modes exhibiting strong magnetic and Fano-like resonances emerge. The use of identical spheres simplifies cluster assembly and facilitates the fabrication of highly symmetric structures. Dielectric spacers are used to tailor the interparticle spacing in these clusters to be approximately 2 nanometers. These types of chemically synthesized nanoparticle clusters can be generalized to other two- and three-dimensional structures and can serve as building blocks for new metamaterials.
and here’s a link to the full text of the article. As with lasers when they were first introduced, it’s a challenge to the imagination to envision how this might be used or applied. What possible medical imaging applications could this be exploited for? That’s the billion dollar question 🙂
This isn’t exactly a surprise, but worth mentioning anyway:
Before the ink was dry on the government’s 2007 budget (or even completed for that matter), the Bush administration’s proposal for the 2008 budget was submitted on February 5th, and the news for biomedical researchers was not very good. According to sources the NIH is slated to receive a $500 million budget cut, before inflation is factored in—assuming a bill inflating their budget for 2007 passes through congress.
Making this even more dire for biomed researchers is the fact that over 10,000 NIH extramural grants are up for renewal in 2008. Those contending for extensions or renewals of such grants are now faced with double difficulty: less money to go around and more people vying for the same number of spaces. Constraints such as these have driven the average age of first-time grant recipients to over 40 years old, barely a young researcher anymore.
The simple truth is that the NIH is probably the single greatest investment of public funds apart from NASA in terms of knowledge generation for the benefit of society that the world has ever seen. Less funds mean less research; less Ph.D.s choosing an academic career; less innovation and less risk-taking. That means more orthodoxy, entrenched and defensive peer-review, and ultimately more echo-chambering.
Even with new funding programs aimed at transitioning postdocs to faculty, it’s hard to justify doing a post-doc to people in the field nowadays – if they have the flexibility, they can make more than double the salary working for industry. What does the future of our field, medical physics and MRI in particular, look like?
Matt McIntosh, writing at Gene Expression, proposes The Lamp Post rule for discussions of science and science policy. Simply stated, “All arguments conducted in a state of relative ignorance must be algebraic.” Head over to GNXP for details.
I missed “Just Science” week by a couple of weeks, so here is my post to try to make up for it:
I have recently been reading a book called “Junk Science” by Dan Agin, who describes himself as a neuroscientist and biophysicist. The book discusses the many ways that legitimate science is twisted/altered/slanted so that the information reaching the public often bears no resemblance whatsoever to the actual science. This happens with environmental pollution, health issues, and genetically engineered food, and just to name a few. Perhaps blame can be placed on the media, politicians, large corporations, etc., but it seems there is another very important underlying issue, here, and that is the scientific literacy of the American public.
Without the basic tools of healthy skepticism and a basic knowledge of science, the “Average Joe” has no hope of understanding the filtered science that appears in the news. As scientists, why should we care? We have ways to communicate amongst ourselves, within the scientific community, but it seems the scientific community also has a responsibility to relate our work and findings to the Average Joe. So many issues — vaccinations for teenage girls against HPV, what food additives are controlled by the government, pollution guidelines for corporations — are decided by non-scientists and affected largely by politicians and lobbyists. In order for the work we do as scientists to go from being purely academic to improving everyday life, the public has to be on board. For them to be on the side of science, they have to understand it.
It seems that as scientists, we have a dire interest in ensuring the scientific literacy of everyone. So, the next time someone asks you to speak to a group of students or write an article for a “non-scientific” newsletter-type publication, think about where most people get their science information. Would you rather have them get it from you, a scientist, or from a CNN article that has been re-interpreted by several laypersons before reaching the public.
By the way, although I don’t agree with all of what Dr. Agin says, he raises several interesting points. It’s very thought-provoking.
The Atlantic Monthly has opened its extensive archives in honor of its 150th birthday. The collection is organized into broad categories, including traditional ones like religion, politics, and women’s rights; there are also more intellectual ruminations like idealism and practicality and markets and morals. Naturally there are technology and science categories as well, and the latter has particular items of interest like this contemporary review of Darwin’s Origin of Species, an essay on Mars by Percival Lowell, and a rumination on the philosophic impact of atomic physics by Warner Heisenberg.